Machine for assembling an insecticidal device

ABSTRACT

Machine for impregnating absorbent sheets and inserting them in receptacles comprises a conveyor passing said sheets through an oven to dry them, a rotating table carrying a plurality of presses for receiving and impregnating the dried sheets, and an assembly line comprising a conveyor belt, means for placing a receptacle half on the belt, followed by an impregnated sheet and a second receptacle half, and means for squeezing the resulting stack to produce a complete receptacle enclosing an impregnated sheet.

United States Patent Foirest 1 Feb. 29, 1972 MACHINE FOR ASSEMBLING ANINSECTICIDAL DEVICE Inventor: Jacques Fcirest, Monfermeil, FranceL'Oreal, Paris, France Aug. 10, 1970 Assignee:

Filed:

Appl. No.:

Foreign Application Priority Data Sept. 16, 1969 France ..693 1461 11.8.C1 ..53/53, 53/111, 53/127 Int. Cl. ...B65b 57/02, B6Sb 63/08 Field ofSearch ..53/53, 111, 127

llllllll llllllllll [56] References Cited UNITED STATES PATENTS2,232,783 2/1941 Hausheer ..53/1 11 R X 2,913,862 11/1959 Sabee PrimaryExaminer-Travis S. McGehee Attorney-Holcombe, Wetherill & Brisebois [57]ABSTRACT Machine for impregnating absorbent sheets and inserting them inreceptacles comprises a conveyor passing said sheets through an oven todry them, a rotating table carrying a plurality of presses for receivingand impregnating the dried sheets, and an assembly line comprising aconveyor belt, means for placing a receptacle half on the belt, followedby an impregnated sheet and a second receptacle half, and means forsqueezing the resulting stack to produce a complete receptacle enclosingan impregnated sheet.

17 Claims, 4 Drawing Figures e 2e TN 38 42 4 3 4 Patented Feb. 29, 19723 Sheets-Sheet 1 Patented Feb. 29, 1972 5 Sheets-Sheet 2 Patented Feb.29, 1972 3 Sheets-Sheet 5 MACHINE FOR ASSEMBLING AN INSECTICIDAL DEVICESUMMARY OF THE INVENTION Certain insecticidal products tend to evaporatewhile emitting toxic vapors, and the size of the zone of toxicity is afunction of the size of the surface over which the insecticidal productis in contact with the atmosphere. In order to improve the efficacy ofsuch liquid insecticides, it has been suggested that small sheets ofabsorbent material be impregnated therewith and a particularinsecticidal sheet has been proposed which consists of an absorbentsupport impregnated with a mixture of an active compound such as'dimethyldichlorovinyl phosphate and a liquid chlorinated terpene havinga very high viscosity. In order to permit efficacious evaporation of theactive insecticidal compounds carried by such absorbent materials, ithas been suggested that a receptacle for the insecticidal sheet or thelike he provided which is made in two parts which are partially hollow.This receptacle also comprises in combination male and female memberslocated on each of the two parts so as to position them relatively toeach other by reciprocal interfitting, and hook members which permit thetwo parts to be snapped together.

It is the object of the present invention to provide an automaticmachine for continuously impregnating sheets of absorbent material andintroducing them into receptacles which said sheets are adapted to fit.It should be emphasized that the absorbent sheets must be introducedinto their receptacles quite rapidly because of the large commercialmarket for this product and the small cost for putting together theassembly consisting of the receptacle and its insecticidal sheet whichis commercially acceptable. Moreover it is advantageous to provide anautomatic machine for this type of assembly work because of the relativetoxicity of the chemical products impregnating the sheets of absorbentmaterial, to which product the laborers would be continuously exposed ifthe process could not be carried out without manual intervention.

It is accordingly an object of the present invention to provide as a newarticle of manufacture a machine adapted to impregnate sheets ofabsorbent material with, for example, an insecticide. This machinecomprises, means for feeding the sheet of absorbent material, whichmeans consists of an endless carrier which traverses a tunnel oven at atemperature high enough to insure that the plates of absorbent materialare dried without being damaged. The machine also comprises a device forimpregnating the sheets of absorbent material introduced by theaforesaid feeding means. This impregnating device consists of a rotatingtable carrying at least one press, between the two plates of which theabsorbent material is introduced. The two plates of the press areadapted to grip the sheet between them and distribute thereover thechemical product with which they are tobe impregnated. Finally, thedevice comprises an assembly line consisting of an endless belt made ofsupports placed side by side and connected to each other, said supportsfirst receiving from a first distributor one of the components of thereceptacle in which the sheet is to be placed, and then receiving fromtransfer means the impregnated sheets issuing from the impregnatingdevice, and finally receiving from a second distributor the second component of said receptacle, which is attached to the first by means of apress positioned in alignment with the assembly line.

In a preferred embodiment of the invention the feeding means comprisesan endless chain traveling over a pair of drums, one at each end of thepath of travel. This chain carries supports perpendicular to its path oftravel. The feeding chain moves step by step and it advances at eachstep through a distance equal to the distance between two adjacentsupports on the chain. The tunnel oven through which the feed chainpasses is at a temperature between 110 and 150, and preferably about130. It takes from 3 to 5 minutes for an article to pass through thefurnace, depending upon the temperature selected. Transfer means ispositioned between the feed means and the impregnating means andcomprises two parallel moving belts on each of which one of the edges ofthe sheets leaving the furnace rest. The supports on the chain passbetween the two belts, which are driven in a direction which brings thesheets toward the impregnating device. The impregnating device comprisesseveral impregnating presses regularly spaced about the rotating table.This table is intermittently rotated to produce an angular displacementequal to the angular distance between two adjacent presses. They aredriven at the same frequency as the feed chain. The rotating table ofthe impregnating device carries the lower stationary plates of theimpregnating presses and the upper plates of said presses are actuatedby movement of a lever in a direction perpendicular to the plane of therotating table. This movement is caused by contact with a stationarycircular cam. The upper and lower plates of each impregnating presscomprise surface sheets of sintered metal or porcelain, one face ofwhich comes in contact with the sheet of absorbent material while theother face defines an injection cavity supplied through a metering pump.The injection cavities are fed at a pressure between 2 and 3 kgJcmF,with equal quantities being injected through the upper plate and thelower plate of the press. The cavities are supplied only when the pressis closed, with the two sintered metal sheets of each press gripping thesheet of absorbent material. Each of the lower and upper plates of animpregnating press is connected to a metering pump which injects intothe injection cavity of the corresponding plate half the quantity of theproduct with which each sheet is to be impregnated. The metering pumpsare valved pumps actuated by the passage of a movable member over astationary cam. These pumps are all carried by the rotating table of theimpregnating device. The metering pumps are supplied from a reservoirhaving a constant level, which is substantially equal to that of thevalves of said pumps. The impregnating device comprises eight presses,five of which are simultaneously in closed position. The sheets aresupplied and ejected at positions situated at from each other, and theedges of the sheets project outside the plates of the impregnatingpresses. The sheets are ejected from the presses by an ejector acting onthe edges of the sheet outside the plates of the press, which ejector isactuated by an eccentric synchronized with the rotation of the rotatingtable. Transfer means at the output of the impregnating device comprisesa stationary grill and a movable grill actuated for translationalmovement by two connecting rods. The bars of the movable grill passbetween the bars of the fixed grill. The transfer means also comprisesdrive rollers which turn about their axis, and over which theimpregnated sheets travel. The transfer means is positioned between theimpregnating device and the conveyor belt and leads the impregnatedsheets to a centering device which positions the sheets with respect tothe support "at the right of said sheets which support already carriesthe lower part of the receptacle for the sheet. Each support on theconveyor belt carries a positioning pin. The conveyor belt comprises,between the second distributor and the press which fastens the two partsof the receptacle together, control means for relatively positioning thecomponents of the receptacle and the sheet with respect to each other.

The press is followed by a hydraulic cylinder which laterally feeds tabswhich may be attached to one side of the assembly of the receptacle,after closing thereof by pressing the two elements thereof against eachother. These tabs are adapted to maintain the equilibrium of thereceptacle in a desired position at its moment of use. The combinationof the movements of the feeding chain, the rotating table, theimpregnating device, the movable grill and the transfer means at theoutput of the impregnating device, and the conveyor belt aresynchronized by a single programmer, for example a cam-type programmer.

In order that the invention may be better understood, a preferredembodiment thereof will now be described, purely by way of illustrationand example, with reference to the accompanying drawings on which:

I 1v- 1v of FIG. 1.

In the example which will now be described a sheet about 12.5 cm. squarewill be impregnated. This sheet consists of cardboard made from a cottonand asbestos base. Each sheet is about 3.5 mm. thick and is impregnatedwith a mixture having insecticidal properties which evaporates slowly.This mixture consists of 10 to 40 percent dimethyldichlorovinylphosphate and 90 to 60 percent of chlorinated terpene, such as is soldunder the trademark STROBANE. Each sheet is impregnated with 30 grams ofthis mixture.

The receptacle in which the sheet impregnated in this manner must beinserted comprises two identical members adapted to be snap-fastenedtogether, with each of said members forming one half of the receptacleand consisting essentially of parallel strips forming a grating. Saidreceptacle comprises a lateral tab adapted to hold it in position whenit is placed in use. This tab is made of a plastic such aspolypropylene.

Referring now to the drawings, it will be seen that reference numeral 1indicated the feeding means for the machine as a whole, while referencenumeral 2 indicates the impregnating device and 3 indicates the conveyorbelt on which the sheet is positioned between the two components of thereceptacle which is to contain it.

The feeding means 1 comprises an endless chain 4 turning at its two endsover two drums 5 and 6. The chain 4 carries supports 7 which projectperpendicularly to its path of travel and are spaced from each other bya distance of several centimeters. The drum 5 drives the chain 4 in anintermittent step-by-step manner. At each step the chain advances by adistance equal to the distance between two successive supports. At theright of the drum 6 is a distributor 8 where the sheets 9 which are toreceive the insecticidal product are stacked. The distributor 8 may bereplaced by a hand feed. Between the drums 5 and 6 is an oven 10 throughwhich the upper lap of the endless chain 4 passes, that is to say thepart of this chain on which the sheets 9 are positioned between thesupports 7.

The temperature of the oven 10 is 130 C. Its length is so calculated,with reference to the speed of movement of chain 4, that the sheets 9remain about 4 minutes inside the furnace. When they reach the end ofthe chain 4 near the drum 5 the sheets 9 have been dried as aconsequence of their passage through the oven 10. This drying isnecessary to avoid hydrolysis of the product impregnating the sheet bythe water initially contained in the absorbent material constituting thesheet. The sheets 9 which have been dried in this manner are placed ontransfer means consisting of two parallel belts, l1a-l 1b, which beltstravel around three pulleys 12, 13 and 14. The portion of the beltsbetween the pulleys l2 and 13 is horizontal. The pulley 14 drives thetwo belts 11a and 11b in the direction indicated by the arrow in FIGS. 1and 2. The supports 7 pass between the edges of the belts and traveltoward the impregnating device 2. Above the belts 11a and 11b is aroller 120 which is rotatably driven in order to assist in driving thesheets 9. In certain cases extracting means controlled by a pneumaticjack may be used to push the sheets 9 in the direction in which thebelts 11a and 11b of the transfer means are moving.

The impregnating device 2 comprises a rotating horizontal table 15, theaxis of rotation 16 of this table being vertical. The table carrieseight identical presses 17 distributed about its periphery. Each press17 consists of a lower plate 17a which is stationary and supported bythe table 15 and a movable upper plate 17b actuated by a set of levers18, 19, 20, with the lower part of lever 20 engaging a circular cam 21through a roller 22. The table 15 may be rotated intermittently inangular steps of 45. When the table is in rest position, one of thepresses 17 is located in axial alignment with the transfer meansconsisting of the belts 11a and 11b. The movement of the table 15 issynchronized with the movement of the chain 4 so that a sheet 9 isplaced on the belts 11a and 11b when the table 15 is at rest, and thetable is rotated through an angle of 45 only after the sheet 9 mountedon the belts 11a and 11b has been engaged between the plates 17a and 17bof the press 17 in axial alignment with the transfer means.

The profile of the cam 21 is such that the press 17 in axial alignmentwith transfer means Ila-11b is open while the press 17 at 45 to thisposition in the direction of rotation of the table shown on FIG. 1, isclosed. The presses 17 between the said 45 position and the 225 positionfrom the position of the press in alignment with the transfer meansIla-11b (said angles being taken in the direction of rotation of thetable 15) are all closed. The three other positions of the press 17 areall, on the contrary, open. The plates 17a and 17b of presses 17 areprovided with a support, which is substantially square when seen inplan, and inside which is a central injection cavity of small volume,which cavity is closed by a sintered steel sheet. The sintered steelsheets carried by the two plates 17a and 17b are face to face. Theinjection cavities of the two plates are supplied through flexibletubing 23a-23b connected to the plates 17al7b respectively. Theseflexible tubes 23a-23b are each connected to a metering pump 26. Thepumps 26 are supported by the rotating table 15 and are valve pumps,controlled by a movable member associated with each pump and in contactwith the stationary cam. The metering pumps 26 are supplied from aconstant level reservoir 27. This level lies substantially in the samehorizontal plane as the valves of the pumps 26. The pumps 26 aresupplied only when the presses corresponding to the pumps are in closedposition. The reservoir 27 contains the insecticidal product with whichthe sheets 9 are to be impregnated. This product is injected through thetubes 23a-23b in back of the sintered metal sheets under a pressure of2.8 kg./cm. The plates 17a and 17b are closed and grip between them asheet 9. It should be noted that the dimensions of the sheets 9 areslightly greater than the dimensions of the plates 17a, 17b so that theedges of these plates are not gripped between the plates of the pressand only the central part of the sheet is impregnated.

The product contained in the reservoir 27 passes through the sinteredmetal surface and is absorbed by the sheet 9. During one revolution ofthe table 15 through 45 25 to 30 g. of the product is injected each 1.5seconds in each sheet 9. When the sheet 9 inside a press 17a has gonethrough three-quarters of a revolution of the rotating table, the press17 is again opened by the cam 21. At this moment, an arm 28 positionedon the part of the plate 17a furtherest from the center of the rotatingtable 15 is struck by a lever 29 at the bottom of the table 15. Thelever 29 is actuated by an eccentric 30 and a spring 31. The arm 28actuated by the lever 29 moves in guides formed in the table 15 parallelto the radius on which the center of the press with which said support28 is associated lies. It is obvious that the drive means 29, 30, 31 arestationary and situated in alignment with the position which the press17 occupies after having passed through three-quarters of a revolutionfrom the position which this press occupied when it received a sheet 9from the transfer means formed by the belts 1 la and 11!).

Transfer means 32 is positioned perpendicularly to the axis of thetransfer means formed by the belts 11a and 11b. The transfer means 32comprises a stationary grill 33, the bars of which are perpendicular tothe axis of the transfer means 32 and a movable grill 34 actuated fortranslational movement by two shafts 35 and 36 through two connectingrods 35a and 36a. The grill 34 remains constantly horizontal in thecourse of this movement. The bars of the grill 34 pass between the barsof the fixed grill 33. At the end of this pair of grills 33 and 34, onthe side remote from the impregnating means 2, is an assembly of rollers37 rotated by a motor 37a. The grill 33 is IIHA'I: mum

attached to electrical weighing means which makes it possible to verify,when the impregnated sheets 9 are positioned thereon, that theimpregnation of said sheets is in fact sufficient.

At the output of this transfer means 32, that is to say on the sideremote from the impregnating device 2, is centering means 38, whichreceives the impregnated plates from the transfer means 32, positionsthem, and places them in alignment with the assembly line 3. Theassembly line 3 comprises a conveyor belt 3a carrying substantiallysquare supports 39. At the four corners of each support 39 arepositioning pins 40. The square defined by the four pins 40 of a support39 corresponds exactly to the dimensions of a receptacle which is toreceive the sheet 9. The assembly line comprising the conveyor belt 3aand its supports 39 travels from a vertical distributor 41 on which thelower parts 42 of the receptacle in which the impregnated sheets 9 areto be inserted are stacked. The conveyor belt then passes under thecentering device 38. This device consists of two U-shaped supports 43,one of the arms of the supports being attached to the piston 44 of apnuematic cylinder 45, while the other arms of the supports are formedby rollers 46 driven by a motor and a set of belts and pulleys. Thesupports 43 are pivotally mounted to turn about an axis 47 positioned atthe point at which the center parts of the supports 43 are connected tothe arms of those supports which are connected to the piston 44. When asheet 9 is brought to the centering position 38 by the transfer means32, this sheet rests on the rollers 46 which drive it up against anabutment and thus insure its accurate positioning. At this moment thehydraulic cylinder separates the rollers 46 by turning the supports 43about this axis 47. The sheet 9 falls vertically in a well definedposition and is located exactly in the central part of the lower member42 of thereceptacle adapted to receive it. it is obvious that theconveyor belt 3a is driven intermittently step by step, with each stepequal to the distance which separates two successive supports 39. Thechain is stopped with one support 39 in alignment with the distributor41 and another support 39 in alignment with the centering means 38.

A support 39 carrying a lower member of thereceptacle 42 and theimpregnated sheet 9 is then led in two successive steps to a positionbeneath a distributor 48 supplying the upper members 49 of thereceptacle in question. This distributor causes a member 49 to bepositioned on the stack formed by the member 42 and the sheet 9. Beyondthe distributor 48 in the direction of advancement of the conveyor belt3 is a control device comprising a photoelectric cell 50 which makes itpossible to verify the proper relative positioning of the members 42, 9and 49. These three components, after two steps by the conveyor belt 3,come into alignment with a press 51 which snaps the members 49, 42together. The press 51 is actuated by a pneumatic cylinder 52. Beyondthe press 51 along the path of travel of the conveyor belt is a device53 which attaches a tab 54 to the side of the receptacle which has beenassembled by the press 51. This attaching step is effectuated by meansof a hydraulic cylinder. The receptacle is then dropped from the end ofthe conveyor belt 3 through a passage 55 leading in the direction of thewrapping machine. The machine according to the invention may also beprovided with a selecting and ejecting device at the end of the conveyorbelt 3 for ejecting the receptacles. Such a device may also, of course,be positioned upstream of the passage 55. It should be noted that themovements of the supply chain, the rotating table, and the conveyor beltare synchronized by a cam type programmer.

The machine which has just been described operates as follows:

The sheets of absorbent material 9 mounted on the distributor 8 arelocated between two supports 7 on the chain 4 and stay inside the oven10 for 4 minutes.

The chain 4 moves step by step, with each step equal to the distancebetween two successive supports 7. At the output of the oven 10 thesheet 9 is dried. It is then positioned by the chain 4 on the belts 11aand 11b which are driven by the pulley 14. The sheet 9, after being thuspositioned, is inserted between the plates 17a and 17b of the press 17,which is in axial alignment with the transfer means formed by the beltsIla-11. The table 15 is driven in rotation in angular steps of 45. Atthe beginning of the first step, the two plates 17a and 17b of the press17 close on the sheet 9, the edges of which extend beyond these plates.The injection cavities behind the sintered metal surfaces of each of theplates 17a and 17b are fed at a pressure of 2.8 kg./cm. through thetubings 25, the rotating distributor 24, and the passages 23a and 23b,with an insecticidal product contained in the reservoir 27. This supplyis maintained until the press 17 is about to open, and is discontinued alittle before the sheet 9 has traveled three-fourths of a revolutionaround the rotating table 15. When the sheet 9 has completedthree-fourths of a revolution, the press 17 is opened, and the arm 28pushes the sheet 9 in the direction of the transfer means 32, as aconsequence of the action of the lever 29 on the arm 28. Sheet 9 is thusmoved onto the bars of the fixed grill 33. The movable grill 34 advancesthe impregnated sheet 9 in several steps along the axis of the transfermeans 32. The sheet thus reaches the rotating rollers 37 and passes fromthem into the centering device 38.

A support 39 on the conveyor belt 3, after having been loaded with thelower component of the receptacle 42 by the distributor 41, reaches aposition beneath the centering device 38. Centering is effectuated bythe rollers 46 which are power driven and force the sheet 9 against thestop. The piston 44 of cylinder 45 then acts on the supports 43 toseparate the rollers 46. The impregnated sheet 9 falls inside the lowermember of the receptacle.

In the course of the step-by-step advancement of the conveyor belt 3,the assembly comprising the member 42 and the sheet 9 comes intoalignment with the second distributor 48, which adds to this assemblythe upper member 49 of the receptacle, and then into alignment with thepress 51 which snaps the two members 42 and 49 together. The device 53then attaches the tab 54. The insecticide dispenser thus completed isremoved in the direction of the wrapping machine through the passage 55.

it will, of course, be appreciated that the embodiment which has justbeen described has been given purely by way of illustration and exampleand may be modified as to detail without thereby departing from thebasis principles of the invention. ln particular, the parts of themachine in which the impregnated sheets are found, as -well as theimpregnating device, may be placed inside a ventilated casing to preventany toxic contamination due to the impregnating product.

, What is claimed is:

1. Machine for impregnating sheets of absorbent material with a liquidand for inserting each sheet in a receptacle consisting of two partsadapted to be snap-fastened together, with each of said parts formingone side of the receptacle, said machine comprising a device for feedingin the sheets of absorbent material, which feeding device comprises anendless conveyor which passes through an oven maintained at atemperature sufficient to dry the sheets of absorbent material withoutcausing deterioration thereof, a device for impregnating the sheets ofabsorbent material supplied by the said feeding device, whichimpregnating device comprises a rotating table carrying at least onepress having a pair of plates between which successive sheets ofabsorbent material are introduced, the two plates of the press beingadapted to grip said sheets between them and to distribute therethroughthe liquid product with which the sheet is to be impregnated, and anassembly line chain comprising conveyor means provided withlongitudinally spaced supports adapted to receive a receptacle part, afirst distributor positioned to place a first receptacle part on eachsupport as it passes by, transfer means downstream of said firstdistributor positioned to transfer an impregnated sheet from said tableto a position on a support above said first receptacle part and a seconddistributor downstream of said transfer means positioned to deposit asecond part of said receptacle on each support above said Insane Annasheet and first part, and a press positioned downstream of said seconddistributor to press the two parts of said receptacle together.

2. Machine as claimed in claim 1 in which the feeding device is formedof an endless carrier travelling over two spaced drums, said belt beingequipped with supports perpendicular to its path of travel.

3. Machine as claimed in claim 2 in which the feeding means is actuatedstep by step, with the length of a step being equal to the distancebetween two adjacent supports on the chain.

4. Machine as claimed in claim 1 in which the oven through which thefeeding conveyor passes is set for a temperature between 110 and 150 C.,said feed conveyor operates at a speed such that a sheet thereon takes 3to 5 minutes to pass through the furnace, depending upon the temperatureof the furnace.

5. Machine as claimed in claim 1 comprising transfer means between thefeeding device and the impregnating means, which transfer meanscomprises two parallel movable belts spaced to carry the edges of sheetsleaving the oven so that the supports of said endless conveyor passbetween the two belts.

6. Machine as claimed in claim 1 in which the impregnating devicecomprises a plurality of impregnating presses regularly spaced about therotating table, and means for driving said table in rotation step bystep through an angle equal to the angular distance between two adjacentpresses, at the same frequency that the feeding device is operated.

7. Machine as claimed in claim 1 in which the rotating table of theimpregnating device carries the lower stationary plates of theimpregnating presses and the upper plates of these presses are actuatedby lever means for movement in a direction perpendicular to the rotatingtable, said lever means being actuated by contact with a stationary cam.

8. Machine as claimed in claim 1 in which the upper plate and lowerplate of each impregnating press comprise sheets of sintered metal orporcelain, one face of which comes in contact with the sheets ofabsorbent material, whereas the other face defines one side of aninjection cavity supplied by a metering pump, each plate of the pressbeing connected to an individual metering pump supplied from a constantlevel reser- 9. Machine as claimed in claim 8 in which the injectioncavities are supplied with impregnating fluid under a pressure ofbetween 2 and 3 kg./cm. with equal quantities injected into the upperand lower plates of the press, said injection taking place only when thetwo plates grip a sheet of absorbent material therebetween.

10. Machine as claimed in claim 6 in which the impregnating devicecomprises eight presses, five of which are simultaneously in closedposition, and sheets are supplied from said feeding device and removedover said transfer means at positions spaced 270 from each other.

11. Machine as claimed in claim 7 comprising means for ejecting saidsheets from the presses including an arm positioned to engage an edge ofa sheet which projects outside the plates of the press, said arm beingactuated by eccentric means which rotates with the rotating table.

12. Machine as claimed in claim 1 in which said transfer means comprisesa stationary grill and a movable grill actuated for translationalmovement, the bars of the movable grill passing between the bars of thestationary grill, and the stationary grill being attached to electricalbalancing means.

13. Machine as claimed in claim 12 in which the transfer means betweenthe impregnating device and the conveyor means in said assembly linecomprises drive rollers which are positively driven and on which theimpregnated sheets travel.

14. Machine as claimed in claim 12 in which the transfer means betweenthe impregnating device and the conveyor means in the assembly lineleads the impregnated sheets to a centering device which positions thesheets with respect to a conveyor support in alignment with said sheeton which one part of said receptacle is already positi oned.

15. Machine as claimed in claim 14 in which each support in the assemblyline carries positioning pins.

16. Machine as claimed in claim 1 in which the assembly line comprisesbetween the second distributor and the press for assembling the twocomponents of the receptacle, control means for positioning thecomponents of the receptacle and the sheet with respect to each otherand ejection means for ejecting defective assemblies.

17. Machine as claimed in claim 1 in which the press in the assemblyline comprises lateral feeding means for bringing in tabs adapted to befastened to the assembled receptacle after closing thereof said tabsbeing adapted to maintain the position of the receptacle when in use.

1. Machine for impregnating sheets of absorbent material with a liquidand for inserting each sheet in a receptacle consisting of two partsadapted to be snap-fastened together, with each of said parts formingone side of the receptacle, said machine comprising a device for feedingin the sheets of absorbent material, which feeding device comprises anendless conveyor which passes through an oven maintained at atemperature sufficient to dry the sheets of absorbent material withoutcausing deterioration thereof, a device for impregnating the sheets ofabsorbent material supplied by the said feeding device, whichimpregnating device comprises a rotating table carrying at least onepress having a pair of plates between which successive sheets ofabsorbent material are introduced, the two plates of the press beingadapted to grip said sheets between them and to distribute therethroughthe liquid product with which the sheet is to be impregnated, and anassembly line chain comprising conveyor means provided withlongitudinally spaced supports adapted to receive a receptacle part, afirst distributor positioned to place a first receptacle part on eachsupport as it passes by, transfer means downstream of said firstdistributor positioned to transfer an impregnated sheet from said tableto a position on a support above said first receptacle part and a seconddistributor downstream of said transfer means positioned to deposit asecond part of said receptacle on each support above said sheet andfirst part, and a press positioned downstream of said second distributorto press the two parts of said receptacle together.
 2. Machine asclaimed in claim 1 in which the feeding device is formed of an endlesscarrier travelling over two spaced drums, said belt being equipped withsupports perpendicular to its path of travel.
 3. Machine as claimed inclaim 2 in which the feeding means is actuated step by step, with thelength of a step being equal to the distance between two adjacentsupports on the chain.
 4. Machine as claimed in claim 1 in which theoven through which the feeding conveyor passes is set for a temperaturebetween 110* and 150* C., said feed conveyor operates at a speed suchthat a sheet thereon takes 3 to 5 minutes to pass through the furnace,Depending upon the temperature of the furnace.
 5. Machine as claimed inclaim 1 comprising transfer means between the feeding device and theimpregnating means, which transfer means comprises two parallel movablebelts spaced to carry the edges of sheets leaving the oven so that thesupports of said endless conveyor pass between the two belts.
 6. Machineas claimed in claim 1 in which the impregnating device comprises aplurality of impregnating presses regularly spaced about the rotatingtable, and means for driving said table in rotation step by step throughan angle equal to the angular distance between two adjacent presses, atthe same frequency that the feeding device is operated.
 7. Machine asclaimed in claim 1 in which the rotating table of the impregnatingdevice carries the lower stationary plates of the impregnating pressesand the upper plates of these presses are actuated by lever means formovement in a direction perpendicular to the rotating table, said levermeans being actuated by contact with a stationary cam.
 8. Machine asclaimed in claim 1 in which the upper plate and lower plate of eachimpregnating press comprise sheets of sintered metal or porcelain, oneface of which comes in contact with the sheets of absorbent material,whereas the other face defines one side of an injection cavity suppliedby a metering pump, each plate of the press being connected to anindividual metering pump supplied from a constant level reservoir. 9.Machine as claimed in claim 8 in which the injection cavities aresupplied with impregnating fluid under a pressure of between 2 and 3kg./cm.2, with equal quantities injected into the upper and lower platesof the press, said injection taking place only when the two plates gripa sheet of absorbent material therebetween.
 10. Machine as claimed inclaim 6 in which the impregnating device comprises eight presses, fiveof which are simultaneously in closed position, and sheets are suppliedfrom said feeding device and removed over said transfer means atpositions spaced 270* from each other.
 11. Machine as claimed in claim 7comprising means for ejecting said sheets from the presses including anarm positioned to engage an edge of a sheet which projects outside theplates of the press, said arm being actuated by eccentric means whichrotates with the rotating table.
 12. Machine as claimed in claim 1 inwhich said transfer means comprises a stationary grill and a movablegrill actuated for translational movement, the bars of the movable grillpassing between the bars of the stationary grill, and the stationarygrill being attached to electrical balancing means.
 13. Machine asclaimed in claim 12 in which the transfer means between the impregnatingdevice and the conveyor means in said assembly line comprises driverollers which are positively driven and on which the impregnated sheetstravel.
 14. Machine as claimed in claim 12 in which the transfer meansbetween the impregnating device and the conveyor means in the assemblyline leads the impregnated sheets to a centering device which positionsthe sheets with respect to a conveyor support in alignment with saidsheet on which one part of said receptacle is already positioned. 15.Machine as claimed in claim 14 in which each support in the assemblyline carries positioning pins.
 16. Machine as claimed in claim 1 inwhich the assembly line comprises between the second distributor and thepress for assembling the two components of the receptacle, control meansfor positioning the components of the receptacle and the sheet withrespect to each other and ejection means for ejecting defectiveassemblies.
 17. Machine as claimed in claim 1 in which the press in theassembly line comprises lateral feeding means for bringing in tabsadapted to be fastened to the assembled receptacle after closing thereofsaid tabs being adapted to maintain the position of the receptacle whenin use.